Remember, last week The Notorious told ESPN's Ariel Helwani that he admired Frankie ... and was interested in a bout with the former 145 pound champ.

But, is Frankie -- who declared he was going down to 135 pounds after losing to Max Holloway -- down for that fight?

Hell yes!

"I'm game, he knows I'm game. I'm supposed to go down to bantamweight, but I will obviously delay that for the McGregor fight."

Edgar says Conor's interview actually made him optimistic the fight could finally happen ... after years of talk.

"It gave me hope that maybe I could get a fight with him. I've been trying to fight this guy for a really long time."

McGregor said he was targeting an Octagon comeback before the start of next year ... and Frankie says he wants to fight once more before 2020 rolls around.

So, what's Edgar's message to Conor?

"Hey, lets stop faking the funk, man. Don't just say it. Lets follow through on it and get it done. I'm game. Like I said, any weight, any time. We could really do it anywhere. That's a fight you get remembered for."